1. Field of the Invention
This invention relates to a split nut, and more particularly, to a split nut that facilitates attachment of a valve assembly to an in-wall outlet box of the type used with appliances such as washing machines, ice makers, and the like. The invention is particularly useful where the valve assembly includes a REHAU® PEX hose barb fitting that is pre-attached to the valve inlet.
2. Description of Related Art
In a conventional in-wall outlet box installation for household appliances, at least one water supply valve, preferably a quarter-turn ball valve, is used to provide a controllable flow of potable water to the appliance. Such water supply valves typically have a downwardly extending nipple with a male pipe thread that is inserted through an aperture in the bottom wall of the molded plastic outlet box, after which a nut is threaded upwardly onto the nipple and tightened until it contacts the underside of the bottom wall and securely attaches the ball valve to the outlet box.
In recent years, cross-linked polyethylene (“PEX”) tubing has become popular for use as water supply lines to inlet valves for appliances such as washing machines, ice makers and the like. Such tubing is typically attached to the bottom of the inlet valve assembly by means of an EVERLOC® PEX hose fitting (“REHAU fitting”) marketed by REHAU Incorporated, Leesburg, Va. Until now, the REHAU fitting that has been used when installing outlet boxes has a smooth-walled tubular section at one end and a hose barb at the other. The smooth end and the hose barb end of the fitting are typically separated by a radially extending flange having an outside diameter (“OD”) significantly greater than the OD of either the smooth or hose barb sections. The flange serves as an anchor point for a tool that is used to crimp the PEX tubing to the hose barb. However, because the OD of the flange for a REHAU hose barb fitting of a given nominal diameter (e.g., ½ inch) is larger than the inside diameter (“ID”) of a nut attachable to the male threads of a valve nipple having the same nominal diameter, the nut cannot be passed over the flange to attach the valve assembly to the outlet box if the REHAU fitting and valve nipple are connected prior to attachment of the valve to the outlet box. Therefore, it has been necessary for an installer first to attach the valve to the outlet box using a standard nut, and then to sweat the smooth end above the flange of a REHAU fitting into the bottom of the valve nipple.
A device and procedure are therefore needed that will enable a REHAU hose barb fitting to be manufactured as part of, or to be preattached to, a water supply valve assembly in such manner that the valve assembly can still be attached to an in-wall appliance outlet box by threading a nut into contact with a wall of the box.
Prior art patents disclose “split nuts” that typically have two opposed, internally threaded sections that are hinged or otherwise clamped together to form a circumferentially extending nut that can be quickly installed or released from an externally threaded bolt or shaft. Other patents disclose “split rings” and “snap rings” that are typically single-piece, substantially circular rings having a relatively small arcuate gap that can be widened by flexing the ring slightly during installation or removal. Although they are not typically threaded, split rings or snap rings may have spaced-apart tangs extending either radially inward or outward to prevent them from being displaced axially along the cylindrical shaft or conduit to which they are applied.
U.S. Pat. No. 6,799,930 discloses a spring-biased, quick-release nut. U.S. Pat. No. 6,460,901 discloses a split thread nut assembly for coupling a flanged pipe to a threaded pipe. U.S. Pat. No. 6,402,206 discloses a split ring with inwardly facing bosses that is used in a fitting for plastic tubing. U.S. Pat. No. 6,352,439 discloses a two-part connector for use in electrical junction boxes. The connector comprises an externally threaded portion that can be threaded into a box, and a spring steel snap ring that fits over the threads to hold the connector in the box and resist pull-out forces. U.S. Pat. Nos. 5,836,627, D387,971 and 5,538,299 disclose split nut locking devices, especially for support rods for auto hatchbacks. U.S. Pat. Nos. 5,000,640; 4,274,323; 2,676,509; 1,652,169; 1,366,884 and 1,082,993 all disclose internally threaded split nuts comprising at least two opposed sections that cooperate to define a nut providing full 360° coverage around an externally threaded pipe or bolt. Different mechanisms are provided for holding the two halves together.